{
  Miranda IM: the free IM client for Microsoft  Windows

  Copyright 2000-2004 Miranda ICQ/IM project,
  all portions of this codebase are copyrighted to the people
  listed in contributors.txt.

  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation; either version 2
  of the License, or (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

  Avatar service

  - load and maintain a cache of contact avatars.
  - draw avatars to a given target device context
  - maintain per protocol fallback images

  The avatar service builds on top of Mirandas core bitmap loading service (MS_UTILS_LOADBITMAP).
  However, if imgdecoder.dll is installed in mirandas main or Plugins directory, it can be used
  to support PNG images. The avatar service loads 32bit PNG images and peforms alpha channel
  premultiplication so that these images can be rendered by using the Win32 AlphaBlend() API.

  The cache grows on demand only, that is, no avatars are PREloaded. An avatar is only loaded
  if a plugin requests this by using the MS_AV_GETAVATAR service. Since avatars may update
  asynchronously, the avatar iamge may not be ready when a plugin calls the service. In that
  case, an event (ME_AV_AVATARCHANGED) is fired when a contacts avatar changes. This event
  is also fired, when a contact avatar changes automatically.

  The service takes care about protocol capabilites (does not actively fetch avatars for
  protocols which do not report avatar capabilities via PF4_AVATARS or for protocols which
  have been disabled in the option dialog). It also does not actively fetch avatars for
  protocols which are in invisible status mode (may cause privacy issues and some protocols
  like MSN don't allow any outbound client communication when in invisible status mode).

  - TODO
  - maintain recent avatars (store the last hashes to avoid re-fetching)
  - cache expiration, based on least recently used algorithm.

  (c) 2005 by Nightwish, silvercircle@gmail.com
}

{$IFNDEF M_AVATARS}
{$DEFINE M_AVATARS}

const
  AVS_BITMAP_VALID    = 1;
  AVS_BITMAP_EXPIRED  = 2;    // the bitmap has been expired from the cache. (unused, currently)
  AVS_HIDEONCLIST     = 4;
  AVS_PREMULTIPLIED   = 8;    // set in the dwFlags member of the struct avatarCacheEntry
                              // for 32 bit transparent images when loaded with
                              // imgdecoder. These images can be rendered transparently
                              // using the AlphaBlend() API with AC_SRC_ALPHA
  AVS_PROTOPIC        = 16;   // picture is a protocol picture
  AVS_CUSTOMTRANSPBKG = 32;   // Bitmap was changed to set the background color transparent
  AVS_HASTRANSPARENCY = 64;   // Bitmap has at least one pixel transparent
  AVS_OWNAVATAR       = 128;  // is own avatar entry
  AVS_NOTREADY        = 4096;

type
  PavatarCacheEntry = ^TavatarCacheEntry;
  TavatarCacheEntry = record
    cbSize      : DWORD;    // set to sizeof(struct)
    hContact    : THANDLE;  // contacts handle, 0, if it is a protocol avatar
    hbmPic      : HBITMAP;  // bitmap handle of the picture itself
    dwFlags     : DWORD;    // see above for flag values
    bmHeight    : integer;  // bitmap dimensions
    bmWidth     : integer;
    t_lastAccess: DWORD;    // last access time (currently unused, but plugins should still
                            // use it whenever they access the avatar. may be
                            // used in the future to implement cache expiration
    lpDIBSection: pointer;
    szFilename  : array[0..MAX_PATH-1] of AnsiChar; // filename of the avatar (absolute path)
  end;

  PCacheNode = ^TCacheNode;
  TCacheNode = record
    pNextNode:pCacheNode;
    ace      :TavatarCacheEntry;
//    cs       :RTL_CRITICAL_SECTION;
    loaded   :bool;
    mustLoad :int;
    dwFlags  :DWORD;
    pa_format:int;
  end;

const
  AVDRQ_FALLBACKPROTO            = $0001; // use the protocol picture as fallback (currently not used)
  AVDRQ_FAILIFNOTCACHED          = $0002; // don't create a cache entry if it doesn't already
                                          // exist. (currently not working)
  AVDRQ_ROUNDEDCORNER            = $0004; // draw with rounded corners
  AVDRQ_DRAWBORDER               = $0008; // draw a border around the picture
  AVDRQ_PROTOPICT                = $0010; // draw a protocol picture (if available).
  AVDRQ_HIDEBORDERONTRANSPARENCY = $0020; // hide border if bitmap has transparency
  AVDRQ_OWNPIC                   = $0040; // draw own avatar (szProto is valid, use "" for global avatar)
  AVDRQ_RESPECTHIDDEN            = $0080; // don't draw images marked as hidden
  AVDRQ_DONTRESIZEIFSMALLER      = $0100; // don't resize images that are smaller then the draw area
  AVDRQ_FORCEFASTALPHA           = $0200; // force rendering with simple AlphaBlend (will use FI_Resample otherwise)
  AVDRQ_FORCEALPHA               = $0400; // force with simple AlphaBlend (may use StretchBlt otherwise)

// request to draw a contacts picture. See MS_AV_DRAWAVATAR service description

type
  PavatarDrawRequest = ^TavatarDrawRequest;
  TavatarDrawRequest = record
    cbSize    : DWORD;     // set this to sizeof(AVATARDRAWREQUEST) - mandatory,
                           // service will return failure code if cbSize is wrong
    hContact  : THANDLE;   // the contact for which the avatar should be drawn.
                           // set it to 0 to draw a protocol picture
    hTargetDC : HDC;       // target device context
    rcDraw    : TRECT;     // target rectangle. The avatar will be centered
                           // within the rectangle and scaled to fit.
    dwFlags   : DWORD;     // flags (see above for valid bitflags)
    dwReserved: DWORD;     // for future use
    dwInternal: DWORD;     // don't use it
    clrBorder : TCOLORREF; // color for the border  (used with AVDRQ_DRAWBORDER)
    radius    : byte;      // radius (used with AVDRQ_ROUNDEDCORNER)
    alpha     : byte;      // alpha value for semi-transparent avatars (valid
                           // values form 1 to 255, if it is set to 0 the
                           // avatar won't be transparent.
    szProto   : PAnsiChar;     // only used when AVDRQ_PROTOPICT is set
  end;

const
//  INITIAL_AVATARCACHESIZE = 300;
//  CACHE_GROWSTEP          = 50;
  CACHE_BLOCKSIZE         = 20;
const
  AVS_MODULE  :PAnsiChar = 'AVS_Settings'; // db settings module path
  PPICT_MODULE:PAnsiChar = 'AVS_ProtoPics'; // protocol pictures are saved here

  {
    obtain the bitmap handle of the avatar for the given contact
    wParam = hContact
    lParam = 0;
    returns: pointer to a struct avatarCacheEntry *, NULL on failure
    if it returns a failure, the avatar may be ready later and the caller may
    receive a notification via ME_AV_AVATARCHANGED
    DONT modify the contents of the returned data structure
  }
  MS_AV_GETAVATARBITMAP:PAnsiChar = 'SV_Avatars/GetAvatar';

  {
    obtain a avatar cache entry for one of my own avatars
    wParam = 0
    lParam = szProto  (protocol for which we need to obtain the own avatar information)
      Use "" to global
    returns: pointer to a struct avatarCacheEntry *, NULL on failure
    DONT modify the contents of the returned data structure
  }
  MS_AV_GETMYAVATAR:PAnsiChar = 'SV_Avatars/GetMyAvatar';

  {
    protect the current contact picture from being overwritten by automatic
    avatar updates. Actually, it only backups the contact picture filename
    and will used the backuped version until the contact picture gets unlocked
    again. So this service does not disable avatar updates, but it "fakes"
    a locked contact picture to the users of the GetAvatar service.

    wParam = hContact
    lParam = 1 -> lock the avatar, lParam = 0 -> unlock
  }
  MS_AV_PROTECTAVATAR:PAnsiChar = 'SV_Avatars/ProtectAvatar';

  {
    set (and optionally protect) a local contact picture for the given hContact

    wParam = hContact
    lParam = either a full picture filename or NIL. If lParam = NIL, the service
    will open a file selection dialog.
  }
  MS_AV_SETAVATAR:PAnsiChar = 'SV_Avatars/SetAvatar';

  {
   set a local picture for the given protocol
   
   wParam = (AnsiChar *) protocol name or NULL for all protocols
   lParam = either a full picture filename or NULL. If lParam == NULL, the service
   will open a file selection dialog.
  }
  MS_AV_SETMYAVATAR:PAnsiChar = 'SV_Avatars/SetMyAvatar';

  {
   see if is possible to set the avatar for the expecified protocol
   
   wParam = (AnsiChar *) protocol name
   lParam = 0
   return = 1 if can set, 0 if can't
  }
  MS_AV_CANSETMYAVATAR:PAnsiChar = 'SV_Avatars/CanSetMyAvatar';
  {
    Call avatar option dialog for contact
    wParam = hContact
  }
  MS_AV_CONTACTOPTIONS:PAnsiChar = 'SV_Avatars/ContactOptions';

  {
    draw an avatar picture

    wParam = 0 (not used)
    lParam = pointer to AVATARDRAWREQUEST
    draw a contact picture to a destination device context. see description of
    the AVATARDRAWREQUEST structure for more information on how to use this
    service.
    return value: 0 -> failure, avatar probably not available, or not ready. The
    drawing service DOES schedule an avatar update so your plugin will be notified
    by the ME_AV_AVATARCHANGED event when the requested avatar is ready for use.
    1 -> success. avatar was found and drawing should be ok.
    -1 -> global avatar is incosistent
  }
  MS_AV_DRAWAVATAR:PAnsiChar = 'SV_Avatars/Draw';
//  MS_AV_BLENDDRAWAVATAR = 'SV_Avatars/BlendDraw';

  {
    fired when the contacts avatar changes
    wParam = hContact
    lParam = struct avatarCacheEntry *cacheEntry
    the event CAN pass a NULL pointer in lParam which means that the avatar has
    changed, but is no longer valid (happens, when a contact removes his avatar,
    for example).
    DONT DESTROY the bitmap handle passed in the struct avatarCacheEntry *

    It is also possible that this event passes 0 as wParam (hContact), in which case,
    a protocol picture (pseudo - avatar) has been changed.
  }
  ME_AV_AVATARCHANGED:PAnsiChar = 'SV_Avatars/AvatarChanged';

type
  TContactAvatarChangedNotification = record
    cbSize  :int;     // sizeof()
    hContact:THANDLE; // this might have to be set by the caller too
    format  :int;     // PA_FORMAT_*
    filename:array [0..MAX_PATH-1] of AnsiChar; // full path to filename which contains the avatar
    hash    :array [0..127] of AnsiChar;        // avatar hash (always an empty string by now)
  end;

const
  {
    fired when the contacts avatar is changed by the contact
    wParam = hContact
    lParam = struct CONTACTAVATARCHANGENOTIFICATION *cacn
    the event CAN pass a NULL pointer in lParam which means that the contact deleted its avatar
  } 
  ME_AV_CONTACTAVATARCHANGED:PAnsiChar = 'SV_Avatars/ContactAvatarChanged';

  {
    fired when one of our own avatars was changed
    wParam = szProto (protocol for which a new avatar was set)
    lParam = AVATARCACHEENTRY *ace (new cache entry,
    NULL if the new avatar is not valid)
  }
  ME_AV_MYAVATARCHANGED:PAnsiChar = 'SV_Avatars/MyAvatarChanged';

  {
    Service to be called by protocols to report an avatar has changed. Some avatar changes
    can be detected automatically, but some not (by now only Skype ones)
    wParam = (AnsiChar *)szProto (protocol for which a new avatar was set)
    lParam = 0
  }
  MS_AV_REPORTMYAVATARCHANGED:PAnsiChar = 'SV_Avatars/ReportMyAvatarChanged';

// Bitmap services //////////////////////////////////////////////////////////////////////

  {
    Load an image
    wParam = NULL
    lParam = filename
  }
  MS_AV_LOADBITMAP32:PAnsiChar = 'SV_Avatars/LoadBitmap32';

  {
    Save an HBITMAP to an image
    wParam = HBITMAP
    lParam = full path of filename
  }
  MS_AV_SAVEBITMAP :PAnsiChar = 'SV_Avatars/SaveBitmap';
  MS_AV_SAVEBITMAPW:PAnsiChar = 'SV_Avatars/SaveBitmapW';

  {
    Returns != 0 if can save that type of image, = 0 if cant
    wParam = 0
    lParam = PA_FORMAT_*   // image format
  }
  MS_AV_CANSAVEBITMAP:PAnsiChar = 'SV_Avatars/CanSaveBitmap';

  {
    Returns a copy of the bitmap with the size especified or the original bitmap
    if nothing has to be changed
    wParam = ResizeBitmap *
    lParam = NULL
  }
  MS_AV_RESIZEBITMAP:PAnsiChar = 'SV_Avatars/ResizeBitmap';

{
 * flags for internal use ONLY
}

  MC_ISMASTERCONTACT    = 1;
  MC_ISSUBCONTACT       = 2;
  AVH_MUSTNOTIFY        = 4; // node->dwFlags (loader thread must notify avatar
                             // history about change/delete event)
  AVS_DELETENODEFOREVER = 8;

// Protocol services //////////////////////////////////////////////////////////////////////

{
  wParam=0
  lParam=(const AnsiChar *)Avatar file name or NULL to remove the avatar
  return=0 for sucess
}
  PS_SETMYAVATAR = '/SetMyAvatar';

{
  wParam=Buffer to file name
  lParam=(int)Buffer size
  return=0 for sucess
}
  PS_GETMYAVATAR = '/GetMyAvatar';

  PIP_NONE   = 0;
  PIP_SQUARE = 1;

// Avatar image max size
// lParam = (POINT*) maxSize (use -1 for no max)
// return 0 for success
  AF_MAXSIZE = 1;

// Avatar image proportion
// lParam = 0
// return or of PIP_*
  AF_PROPORTION = 2;

// Avatar format
// lParam = PA_FORMAT_*
// return = 1 (supported) or 0 (not supported)
  AF_FORMATSUPPORTED = 3;

// Avatars are enabled for protocol?
// lParam = 0
// return = 1 (avatars ready) or 0 (disabled)
  AF_ENABLED = 4;

// This protocol don't need delays for fetching contact avatars
// lParam = 0
// return = 1 (don't need) or 0 (need)
  AF_DONTNEEDDELAYS = 5;

// Avatar file max size
// return size in bytes (0 for no limit)
  AF_MAXFILESIZE  = 6;

// The amount of time avs should wait after a download avatar failed for a contact
// lParam = 0
// return = the time, in ms
  AF_DELAYAFTERFAIL = 7;

{
  Query avatar caps for a protocol
  wParam = One of AF_*
  lParam = See descr of each AF_*
  return = See descr of each AF_*. Return 0 by default
}
  PS_GETAVATARCAPS = '/GetAvatarCaps';

{$ENDIF}
